JP7243403B2 - Polyorganosiloxane-containing graft polymer, resin composition containing the same, molding thereof, and method for producing polyorganosiloxane-containing graft polymer - Google Patents

Description

TECHNICAL FIELD The present invention relates to a polyorganosiloxane-containing graft polymer, a resin composition containing the same, and a molded article thereof.

The rubber-containing graft polymer is obtained by graft-polymerizing a vinyl monomer to a rubber-like polymer. A rubber-containing graft polymer is produced by emulsion polymerization, and can be dispersed in a wide variety of resins while maintaining a predetermined rubber particle size and rubber structure. Therefore, it is suitably used for resins that require impact strength.

The particle size of the rubber is preferably 400 nm or less, which is smaller than the visible wavelength of light, in order to achieve a high appearance. In order to improve the impact strength, it is generally required that the elastic modulus of the rubber be low and the Poisson's ratio be high. Therefore, butadiene rubber and silicone rubber are more preferably used than acrylic rubber. Butadiene rubber and silicone rubber represented by polydimethylsiloxane have a high Poisson's ratio of 0.5 and a low elastic modulus.

Butadiene rubber is hardened by heat and ultraviolet rays, and has problems such as being colored. Considering durability, silicone-based rubber is preferable. However, silicone-based rubber is more expensive than butadiene rubber, and when mixed with a resin composition having a high refractive index such as vinyl chloride or polycarbonate resin, the transparency of the molded product is lowered, resulting in a colored appearance, especially a deep color. There are problems such as difficulty in expressing a certain black color.

Patent Document 1 describes a resin composition containing a polycarbonate resin, other thermoplastic resins (AS resin, ABS resin), and a rubber-containing graft copolymer (polyorganosiloxane-containing graft copolymer). there is In the formation of the rubber-containing graft copolymer, the silicone rubber is compounded with a styrene resin to increase the refractive index and improve the strength of the molded article obtained even when the particle size is 400 nm or less.

In Patent Document 2, a silicone monomer is dropped in the presence of a copolymer (core material) of styrene and acrylonitrile to form a latex (rubber particles), and a mixture of styrene and acrylonitrile monomers is added dropwise to the latex. A process for polymerizing and producing graft polymers is described. The obtained graft polymer has a particle size of about 200 nm and has a core/shell particle graft structure, and a molded article of a composition in which this graft polymer and polycarbonate are blended has high low-temperature toughness. It is stated that

JP 2016-117866 A JP-A-1-161049

However, with the technique of Patent Document 1, when polycarbonate is contained alone without adding other thermoplastic resins, the impact strength of the resulting molded article is not sufficient. In addition, impact strength and appearance of the molded article obtained by the technology of Patent Document 2 are not sufficient.
An object of the present invention is to provide a polyorganosiloxane-containing graft polymer capable of improving the strength and appearance of molded articles, and a resin composition containing the same.

According to one aspect of the present invention, a polymer (A) containing a polyorganosiloxane (A1) and a vinyl polymer (A2) is a polyorganosiloxane-containing graft polymer grafted with a vinyl monomer (b). A polyorganosiloxane-containing graft polymer (B) which is a coalescence and which satisfies the requirements of Z-1 to Z-4 below.
Z-1) 15% or more in number average of particles having a structure in which the vinyl polymer (A2) is singly contained in the polyorganosiloxane (A1) Z-2) Tetrahydrofuran-insoluble polyorganosiloxane-containing graft polymer Z-3) The particle size of the polyorganosiloxane-containing graft polymer is 50 to 250 nm
Z-4) The refractive index of the polyorganosiloxane-containing graft polymer is 1.47 to 1.60

According to another aspect of the present invention, there is provided a resin composition comprising the polyorganosiloxane-containing graft polymer (B) and a thermoplastic resin (C).

According to another aspect of the present invention, there is provided a molded article formed using the resin composition.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a polyorganosiloxane-containing graft polymer capable of improving the strength and appearance of molded articles, and a resin composition containing the same.

BRIEF DESCRIPTION OF THE DRAWINGS It is a cross-sectional schematic diagram for demonstrating the structure of the polymer (A) which comprises the polyorganosiloxane containing graft polymer (B) of this invention.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail.

[Polyorganosiloxane-containing graft polymer (B)]
In the polyorganosiloxane-containing graft polymer (B) of the present invention, the "vinyl monomer" (b) is added to the "rubber-like polymer" (A) (rubber latex) obtained in an aqueous medium in the presence of an emulsifier. It is graft-polymerized (graft latex). A component derived from graft polymerization that constitutes the polyorganosiloxane-containing graft polymer (B) is hereinafter referred to as a "graft component". The polyorganosiloxane-containing graft polymer (B) of the present invention satisfies requirements Z-1 to Z-4.

(Core structure: Condition Z-1)
The rubber-like polymer (A) that can be used in the present invention has a structure (hereinafter " (Condition Z-1).

The term "single" as used herein means that the vinyl polymer (A2) contained in the polyorganosiloxane (A1) has a sea-island structure in which the vinyl polymer (A2) is wholly contained in the polyorganosiloxane (A1). and the included vinyl polymer (A2) forms one island.

(Measurement of core structure)
The "core structure" is measured by dispersing the polyorganosiloxane-containing graft polymer (B) in an epoxy resin according to the following procedure, and measuring the ratio (number average) from the image of the section observed with a transmission electron microscope. calculate.
1) A polyorganosiloxane-containing graft polymer (B) is placed on the tip of a polyethylene capsule, and an uncured epoxy resin is poured into the capsule and allowed to stand at room temperature for 12 hours to cure to obtain a resin piece.
2) The obtained resin pieces are cut out using a microtome, and the cut pieces are collected on a copper grid with a support film. The thickness of the section is 50 nm.
3) Acquire images of the sections by transmission electron microscopy. The acquisition magnification of the image is assumed to be 100,000 times.

Among the particles confirmed in the image, 30% of the particles with the largest cross-sectional area are selected, and a total of 100 or more are evaluated (the ratio of the selected particles is the total number of particles confirmed in the image). (refers to the ratio of the number of particles). The evaluated particles were classified into 5 types (S, T, U, V, W) shown in FIG. Among them, the number of particles having a core structure in which the entire core portion was covered as indicated by S in FIG. 1 was counted, and the ratio to the number of particles to be evaluated was calculated. FIG. 1 is a schematic cross-sectional view for explaining the structure of the polymer (A) constituting the polyorganosiloxane-containing graft polymer (B) according to the present invention. In S, T, U, V, and W in the figure, the dark colored portion corresponds to the polyorganosiloxane (A1) phase, and the light colored portion corresponds to the vinyl polymer (A2) phase. S indicates a core structure, that is, it consists of one phase of polymer (polyorganosiloxane) A1 and one phase of polymer (vinyl polymer) A2, and the entirety of one phase of polymer A2 is included in polymer A1. (hereinafter also referred to as “S structure”). T is a structure consisting of one phase of polymer A1 and one phase of polymer A2, and neither phase is included in the other phase (hereinafter referred to as "T structure"). U is a structure (hereinafter referred to as "U structure") consisting of one phase of polymer A1 and two phases of polymer A2, and neither phase is included in another phase. V is a structure consisting of one phase of polymer A1 (hereinafter referred to as "V structure"), and W is a structure consisting of one phase of polymer A2 (hereinafter referred to as "W structure").

In the rubber-like polymer (A) that can be used in the present invention, the ratio of particles having a core structure (S structure) is 15% or more in number average. The number average ratio of particles having a structure including a phase and a polymer A2 phase, in which neither phase is included in the other phase, is preferably 40% or less, more preferably 35% or less. . In addition, the number average proportion of particles having a structure such as a U structure that includes a single phase of polymer A1 and multiple phases of polymer A2, in which none of the phases is included in the other phase, is 10% or less. is preferable, and 5% or less is more preferable. In addition, the W-structure particles are more preferably 5% or less, more preferably 1% or less, in number average.

(THF solubility: Condition Z-2)
In the rubber-like polymer (A) that can be used in the present invention, it is preferable that the polyorganosiloxane (A1) is sufficiently crosslinked and covalently bonded to the vinyl polymer (A2) within the particles. In terms of structure, it is preferably covalently bonded to the core (vinyl polymer (A2)). These can be measured by the degree of dissolution in tetrahydrofuran (hereinafter referred to as "THF"). If the polyorganosiloxane-containing graft polymer (B) has a THF insoluble content of 50% by mass or more (condition Z-2), the polyorganosiloxane (A1) is sufficiently crosslinked and shared with the core of the core structure. can be determined to be connected. Furthermore, the THF-insoluble content of the polyorganosiloxane-containing graft polymer (B) is preferably 60% by mass or more, more preferably 70% by mass or more.

(Method for measuring THF-insoluble matter)
The THF-insoluble matter is measured by first preparing a mixed solution of 1% by mass of the polyorganosiloxane-containing graft polymer (B) and 99% by mass of THF, and performing the following operations (1) to (4). .
(1) Add 0.5 g of the sample to 50 ml (44.5 g) of THF to prepare a mixed solution, and extract the soluble matter with THF at room temperature for about 8 hours. Then, stir with a stirrer at room temperature for 30 minutes or more before centrifugation performed later.
(2) The mixed solution is placed in a centrifugal tube and centrifuged at 16000 rpm for 40 minutes.
(3) After removing the supernatant, THF is added and centrifugation is performed again (this is repeated twice) to wash the insoluble matter.
(4) After removing the supernatant liquid, the insoluble matter (including the centrifugal tube) was dried at a temperature of 80 ° C. for 8 hours, and further dried at 65 ° C. for 6 hours in a vacuum dryer, dried sample (THF insoluble matter) get
The mass (including the centrifugal tube) of the obtained dry sample (THF-insoluble matter) is measured, and the content ratio w _ais (%) of the THF-insoluble matter is calculated according to the following formula.
w _ais =(w _c1 −w _as )/wt×100
wt: Mass of polyorganosiloxane-containing graft polymer (B) subjected to measurement (including THF-insoluble matter)
w _as : Mass of centrifuge tube w _c1 : Mass of THF-insoluble matter (mass including centrifuge tube)

(Particle size: condition Z-3)
The average particle size of the polyorganosiloxane-containing graft polymer (B) according to the present invention is in the range of 50 to 250 nm (Condition Z-3). If the average particle size is in the range of 50 to 250 nm, the impact strength of the molded article can be improved, it is preferably in the range of 70 to 220 nm, and more preferably in the range of 70 to 200 nm.

The average particle size of the polyorganosiloxane-containing graft polymer (B) is 30% (based on number) of the particles with the largest cross-sectional area among the particles confirmed in the image obtained by the above measurement of the core structure. A total of 100 or more particles are selected, and the average particle size is calculated using image analysis software (manufactured by Nippon Roper Co., Ltd., product name: Image Pro Plus). Moreover, the average particle size of the polyorganosiloxane-containing graft polymer (B) can be measured by a light scattering method or a capillary particle size distribution meter.

As a method for making the average particle size 250 nm or less, it is preferable to produce a polyorganosiloxane-containing graft polymer by emulsion polymerization, and by adjusting the amount of emulsifier, a rubber-like polymer having an average particle size of 50 to 250 nm can be obtained. .

(Refractive index: Condition Z-4)
The refractive index of the polyorganosiloxane-containing graft polymer (B) according to the present invention is in the range of 1.47 to 1.60 (Condition Z-4).

(Measurement of refractive index)
The polyorganosiloxane-containing graft polymer (B) is hot-pressed to produce a molded product having a size of 20 mm×8 mm and a thickness of 2 mm, and the refractive index can be measured under the following measurement conditions.
Abbe refractometer: NAR-2 (product name, manufactured by Atago Co., Ltd.),
Measurement conditions: measurement temperature 23 ± 1 ° C, measurement humidity 50 ± 5% RH (relative humidity)

However, if the sample obtained by the heat press is opaque and the accuracy is not sufficient, the polymer that constitutes the polyorganosiloxane-containing graft polymer (B) (polyorganosiloxane (A1), vinyl polymer (A2 ), etc.) can be quantified, and the volume conversion ratio of each refractive index of those polymers can be added for calculation.

The refractive index can also be calculated by measuring as a polymer of vinyl monomers excluding monomers having two or more vinyl units forming covalent bonds with other polymers in a single molecule.

For example, it is calculated using the following formula (1) described in POLYMER HANDBOOK 4th Edition (Wiley Interscience).
n=v1n1+v2n2+v3n3+... Formula (1)
In the formula, “n1, n2, n3, . Refractive Indices of Polymers) literature values (1.49 for polymethyl methacrylate, 1.47 for poly n-butyl acrylate, 1.59 for polystyrene), reported values from various manufacturers (1.40 for polydimethylsiloxane) , and further, the values obtained with the software "Cynthia" of Accelrys can be used. In the formula, "v1, v2, v3, ..." represent the volume fraction of each monomer.

Monomers having two or more vinyl units forming covalent bonds with other polymers in a single molecule include, for example, allyl methacrylate, triallyl cyanurate, triallyl isocyanurate, divinylbenzene, ethylene glycol dimethacrylate, Multifunctional monomers such as propylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,4-butylene glycol dimethacrylate, 1,6-hexanediol diacrylate, and triallyl trimellitate, and siloxane-based graft crossing agents (a2-2) can be mentioned.

If each monomer having two or more vinyl units forming a covalent bond with another polymer in a single molecule accounts for 1% by mass or less of the polyorganosiloxane-containing graft polymer (B), The precision of the refractive index obtained by calculation as a polymer of vinyl monomers excluding the vinyl monomer component that crosslinks or forms a covalent bond with another polymer and the crosslinking agent is sufficiently high. Also, the proportion of monomers having two or more vinyl units forming covalent bonds with all other polymers in a single molecule in the polyorganosiloxane-containing graft polymer (B) is 3% by mass or less. is preferred, and it is more preferably 2% by mass or less.

(Method for producing polyorganosiloxane-containing graft polymer (B))
The method for producing the polyorganosiloxane-containing graft polymer (B) preferably includes the following steps. According to this production method, a structure in which the vinyl polymer (A) is singly included in the polyorganosiloxane (A1) can be formed.

1) A latex (core latex) is produced by polymerizing a vinyl monomer (a2) in an aqueous medium in the presence of an emulsifier. The vinyl monomer (a2) preferably comprises a vinyl monomer (a2-1) and a siloxane-based graft crossing agent (a2-2).
2) The organosiloxane (a1) is added dropwise to this latex and polymerized (to form polymer (A)).
3) A substance having a glass transition temperature of 0° C. or lower can be polymerized between the preceding step (2) and the following step (4).
4) Grafting the resulting polymer (A) with vinyl monomer (b) to form polymer (B).

Hereinafter, as appropriate, the latex obtained in the above step (1) is referred to as "core latex", and the latex obtained in steps (2) to (3) (that is, the latex before performing step (4)) is referred to as "rubber latex. and the latex obtained in step (4) is referred to as "grafted latex".

(vinyl monomer (a2))
The vinyl monomer (a2) is not particularly limited as long as it can form a core latex, but it preferably contains the following vinyl monomer (a2-1) and a siloxane-based graft crossing agent (a2-2). .

(vinyl monomer (a2-1))
Although the vinyl monomer (a2-1) is not particularly limited, it preferably contains a vinyl monomer having a high refractive index and a high glass transition point after polymerization. For example, styrene, α-methylstyrene, phenyl methacrylate, acrylonitrile, vinylidene chloride, p-chlorostyrene, benzyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, 3,3,5-trimethylcyclohexyl methacrylate, isobornyl acrylate, isobornyl methacrylate, Methyl methacrylate, pt-butyl styrene, n-butyl acrylate and the like are preferred. Such vinyl monomers can be used alone or in combination of two or more. The content of such a vinyl monomer is preferably 80% by mass or more, more preferably 90% by mass or more, and is further set to 100% by mass with respect to the total vinyl monomers forming the core latex. be able to.

(Other vinyl monomers)
As other vinyl monomers, the following polyfunctional monomers can be blended if necessary. For example allyl methacrylate, triallyl cyanurate, triallyl isocyanurate, divinylbenzene, ethylene glycol dimethacrylate, propylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,4-butylene glycol dimethacrylate, 1,6-hexane Diol diacrylate, triallyl trimellitate and the like are preferred. Such polyfunctional monomers can be used alone or in combination of two or more. The content of such vinyl monomers is preferably 20% by mass or less, more preferably 10% by mass or less, relative to the total vinyl monomers forming the core latex.

(Siloxane-based graft crossing agent (a2-2))
The siloxane-based graft crossing agent (a2-2) has a siloxy group (--Si--O--) and a functional group polymerizable with a vinyl monomer. Examples of the siloxane-based graft crossing agent (a2-2) include siloxanes represented by formula (I).
R—Si(R ₁ ) _n (OR ₂ ) _(3-n) (I)
In formula (I), R ₁ represents a methyl group, ethyl group, propyl group, or phenyl group. R ₂ represents an organic group in an alkoxyl group, preferably a methyl group, an ethyl group, a propyl group, or a phenyl group. n represents 0, 1 or 2; R represents any group represented by formulas (I-1) to (I-4).
CH ₂ =C(R ₃ )-COO-(CH ₂ ) _p - (I-1)
_CH2 =C _{( R4} ) _-C6H4- (I-2)
CH ₂ =CH- (I-3)
HS—(CH ₂ ) _p − (I-4)
In these formulas, R ₃ and R ₄ each represent a hydrogen atom or a methyl group, and p represents an integer of 1-6.

A methacryloyloxyalkyl group can be mentioned as the functional group represented by formula (I-1). Examples of siloxanes having this group include the following. β-Methacryloyloxyethyldimethoxymethylsilane, γ-Methacryloyloxypropylmethoxydimethylsilane, γ-Methacryloyloxypropyldimethoxymethylsilane (3-Methacryloxypropylmethyldimethoxysilane), γ-Methacryloyloxypropyltrimethoxysilane, γ-Methacryloyloxy propylethoxydiethylsilane, γ-methacryloyloxypropyldiethoxymethylsilane, δ-methacryloyloxybutyldiethoxymethylsilane and the like.

Examples of the functional group represented by formula (I-2) include a vinylphenyl group. Examples of siloxanes having this group include vinylphenylethyldimethoxysilane.

Examples of the siloxane having a functional group represented by formula (I-3) include vinyltrimethoxysilane and vinyltriethoxysilane.

A mercaptoalkyl group can be mentioned as the functional group represented by the formula (I-4). Examples of siloxanes having this group include the following. γ-mercaptopropyldimethylsilane, γ-mercaptopropylmethoxydimethylsilane, γ-mercaptopropyldiethoxymethylsilane, γ-mercaptopropylethoxydimethylsilane, γ-mercaptopropyltrimethoxysilane and the like.

These siloxane-based graft crossing agents (a2-2) can be used singly or in combination of two or more. 3-Methacryloxypropylmethyldimethoxysilane is particularly preferred from the viewpoint of forming particles having a structure that is solely included in the polyorganosiloxane (A1).

The content of the siloxane-based graft-crossing agent (a2-2) is 0.05 to 20% by mass with respect to the total 100% by mass of the vinyl monomer (a2-1) and the siloxane-based graft-crossing agent (a2-2). %, more preferably 0.1 to 10% by mass, even more preferably 0.5 to 5% by mass. If the content of the siloxane-based graft crossing agent (a2-2) is in the range of 0.05 to 20% by mass, the covalent bond between the core portion of the core structure and the polyorganosiloxane can be sufficiently formed, and the impact resistance can be improved. A good polyorganosiloxane-containing graft copolymer (B) can be obtained.

(Radical polymerization initiator)
As the radical polymerization initiator used for the polymerization of vinyl monomers, azo initiators, peroxides, and redox initiators obtained by combining peroxides and reducing agents can be used. These can be used individually by 1 type or in combination of 2 or more types.

Examples of azo initiators include the following. 2,2'-azobis isobutyronitrile, dimethyl 2,2'-azobis(2-methylpropionate), 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis Oil-soluble azo initiators such as (2-butyronitrile), 4,4′-azobis (4-cyanovaleric acid), 2,2′-azobis[N-(2-carboxymethyl)-2-methylpropiona midin] hydrate, 2,2′-azobis-(N,N′-dimethyleneisobutyramidine) dihydrochloride, 2,2′-azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride water-soluble azo initiators such as These can be used individually by 1 type or in combination of 2 or more types.

Examples of peroxides include the following. Inorganic peroxides such as hydrogen peroxide, potassium persulfate and ammonium persulfate, diisopropylbenzene hydroperoxide, p-menthane hydroperoxide, cumene hydroperoxide, t-butyl hydroperoxide, succinic acid peroxide, t- Butyl peroxyneodecanoate, t-butyl peroxyneoheptanoate, t-butyl peroxypivalate, 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate, t-butyl organic peroxides such as peroxy-2-ethylhexanoate; These can be used individually by 1 type or in combination of 2 or more types.

When a redox initiator is obtained by combining a peroxide with a reducing agent, the above peroxide, a reducing agent such as sodium formaldehyde sulfoxylate, L-ascorbic acid, fructose, dextrose, sorbose, inositol, and sulfuric acid It is preferable to use a combination of monoiron/ethylenediaminetetraacetic acid disodium salt. These reducing agents can be used singly or in combination of two or more.

The amount of the radical polymerization initiator used is preferably 0.01 to 1 part by mass with respect to 100 parts by mass of the total monomers when an azo initiator is used. The amount of the peroxide used is preferably 0.01 to 1 part by mass with respect to 100 parts by mass of the monomers.

(rubberization)
In the presence of a core latex (vinyl polymer (A2)) obtained by polymerizing a vinyl monomer (a2), an organosiloxane (a1) is polymerized to form a polyorganosiloxane (A1), and a rubber latex (a polymer The method for obtaining the polymer (A) containing the coalescence A1 and the polymer A2) is not particularly limited, and for example, the following production method can be employed.

First, an acid catalyst is introduced into the core latex. Organosiloxane (a1) or a mixture containing it (including at least one selected from siloxane-based cross-linking agents, siloxane-based graft crossing agents, and siloxane oligomers having terminal blocking groups as components to be mixed as necessary), An emulsion is prepared by emulsifying with an emulsifier and water. After that, the organosiloxane (a1) or a mixture containing it is polymerized at a high temperature while being added dropwise to the core latex. The acid is then neutralized with an alkaline substance to obtain a rubber latex.

Polyorganosiloxane (A1) is a polymer containing units of organosiloxane (a1). The polyorganosiloxane (A1) can be obtained by polymerizing an organosiloxane or an "organosiloxane mixture" containing one or more components used as needed with an organosiloxane. Components used as necessary include at least one selected from a siloxane-based cross-linking agent, a siloxane-based graft-crossing agent, and a siloxane oligomer having a terminal blocking group.

Any of linear organosiloxanes, alkoxysilane compounds, and cyclic organosiloxanes can be used as the organosiloxane (a1). Among them, alkoxysilane compounds and cyclic organosiloxanes are preferred, and cyclic organosiloxanes are particularly preferred because of their high polymerization stability and high polymerization rate.

As the alkoxysilane compound, a bifunctional alkoxysilane compound is preferable, and examples thereof include dimethyldimethoxysilane, dimethyldiethoxysilane, diethoxydiethylsilane, dipropoxydimethylsilane, diphenyldimethoxysilane, diphenyldiethoxysilane, methylphenyldimethoxysilane, Methylphenyldiethoxysilane and the like can be mentioned.

As the cyclic organosiloxane, those having 3- to 7-membered rings are preferable, and examples thereof include hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, trimethyltriphenylcyclotrisiloxane, tetra Mention may be made of methyltetraphenylcyclotetrasiloxane, octaphenylcyclotetrasiloxane. These can be used individually by 1 type or in combination of 2 or more types. Among these, octamethylcyclotetrasiloxane is preferable because the particle size distribution can be easily controlled.

As the organosiloxane (a1), a cyclic dimethylsiloxane and/or a bifunctional dialkylsilane compound is preferable from the viewpoint of obtaining a graft polymer (B) capable of increasing the impact resistance of the molded article.

A cyclic dimethylsiloxane is a cyclic siloxane having two methyl groups on a silicon atom, and examples thereof include hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, and dodecamethylcyclohexasiloxane. These can be used individually by 1 type or in combination of 2 or more types.

A bifunctional dialkylsilane compound is a silane compound having two alkoxy groups and two alkyl groups on each silicon atom, and examples thereof include dimethyldimethoxysilane, dimethyldiethoxysilane, diethoxydiethylsilane, and dipropoxydimethylsilane. . These can be used individually by 1 type or in combination of 2 or more types.

In order to obtain a graft polymer (B) capable of increasing the impact resistance of a molded article, a mixture containing an organosiloxane (a1) and a siloxane-based cross-linking agent is used in forming the polyorganosiloxane (A1). is preferred. Polyorganosiloxane (A1) having a crosslinked structure can be obtained by using a siloxane-based crosslinking agent.

As the siloxane-based cross-linking agent, one having a siloxy group is preferable. Examples of siloxane-based cross-linking agents include tri- or tetra-functional silane-based cross-linking agents such as trimethoxymethylsilane, triethoxyphenylsilane, tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, and tetrabutoxysilane. agents can be mentioned. Among them, a tetrafunctional cross-linking agent is preferable, and tetraethoxysilane is more preferable. The content of the siloxane-based cross-linking agent is preferably 0.5 to 10% by mass, more preferably 1.0 to 5% by mass, based on 100% by mass of the organosiloxane mixture. By adjusting the content of the siloxane-based cross-linking agent to 0.5 to 10% by mass, it is possible to obtain a graft copolymer (B) capable of improving the impact resistance of the molded article.

In the formation of rubber latex (polymer (A) containing polymer A1 and polymer A2), the polymerization reaction of organosiloxane or a mixture thereof is carried out by adding sodium hydroxide, potassium hydroxide, ammonia aqueous solution, etc. to the resulting rubber latex. can be terminated by neutralizing to pH 6-8 with an alkaline substance of .

Acid catalysts used for polymerization of organosiloxanes or mixtures thereof include sulfonic acids such as aliphatic sulfonic acids, aliphatic-substituted benzenesulfonic acids, and aliphatic-substituted naphthalenesulfonic acids, and mineral acids such as sulfuric acid, hydrochloric acid, nitric acid, and phosphoric acid. is mentioned. These acid catalysts can be used singly or in combination of two or more. Among these, when mineral acids such as sulfuric acid, hydrochloric acid, and nitric acid are used, the particle size distribution of the polyorganosiloxane latex can be narrowed. It is possible to reduce the deterioration of the properties and appearance defects.

The amount of the acid catalyst used is preferably 0.005 to 5 parts by weight per 100 parts by weight of the organosiloxane. When the amount of the acid catalyst used is 0.005 parts by mass or more, the polyorganosiloxane can be polymerized in a short time. Also, when the amount of the acid catalyst used is 5 parts by mass or less, it is possible to obtain a molded article having excellent thermal decomposition resistance and appearance.

In addition, since the amount of acid catalyst used is a factor that determines the particle size of polyorganosiloxane, in order to obtain polyorganosiloxane having a particle size described later, the amount of acid catalyst used should be 0.005 to 1.5 mass. Part is more preferable.

(grafting)
The vinyl monomer (b) used for grafting (graft polymerization) to obtain the polyorganosiloxane-containing graft polymer (B) of the present invention is not particularly limited, but examples include styrene, α-methylstyrene, and phenyl methacrylate. , acrylonitrile, vinylidene chloride, p-chlorostyrene, benzyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, 3,3,5-trimethylcyclohexyl methacrylate, isobornyl acrylate, isobornyl methacrylate, methyl methacrylate, pt-butylstyrene, etc. is mentioned.

The vinyl monomer (b) preferably contains methyl methacrylate as a main component, and the content of other components is preferably 5% by mass or less. Examples of other components include aromatic vinyl compounds such as styrene and α-methylstyrene; alkyl acrylates such as methyl acrylate and butyl acrylate; and alkyl methacrylates such as ethyl methacrylate. The vinyl monomer is selected so that the glass transition temperature of the polymer or copolymer obtained by polymerizing the vinyl monomer (b) (either homopolymerizing or copolymerizing two or more in combination) is 70°C or higher. preferably. A glass transition temperature of 70° C. or higher is preferable from the viewpoint of the properties (fluidity and particle size of the powder) of the powder obtained from the subsequent coagulation step.

A polymer having a glass transition temperature of 0° C. or less may be formed prior to graft polymerization of the vinyl monomer (b). Specific examples include the following. Butadiene rubber, styrene/butadiene copolymer rubber, acrylonitrile/butadiene copolymer rubber, acrylic rubber such as polybutyl acrylate, polyisoprene, polychloroprene, ethylene/propylene rubber, ethylene/propylene/diene terpolymer rubber, styrene/ Block copolymers such as butadiene block copolymer rubbers, styrene/isoprene block copolymer rubbers, and hydrogenated products thereof are included.

If a polymer having a glass transition temperature of 0° C. or less is not formed before the graft polymerization, the unsaturated component (vinyl component) derived from the siloxane-based graft crossing agent (a2-2) in the rubber latex and the graft polymerization A graft polymer can be formed with the rubber-like polymer (A) by chemically bonding the vinyl monomer (b) used in the above. In order to increase the graft efficiency, before adding the vinyl monomer (b) used for graft polymerization, for example, allyl methacrylate, triallyl cyanurate, triallyl isocyanurate, divinylbenzene, ethylene glycol dimethacrylate, propylene glycol dimethacrylate, Polyfunctional monomers such as 1,3-butylene glycol dimethacrylate, 1,4-butylene glycol dimethacrylate, 1,6-hexanediol diacrylate, and triallyl trimellitate may be pre-added and polymerized. It is preferable from the viewpoint of the efficiency of graft polymerization with a similar polymer.

The content of the rubber-like polymer (A) in the polyorganosiloxane-containing graft polymer (B) is the ratio of the remaining polymer excluding the polymer component of the vinyl monomer (b) used in the graft polymerization. be. The content of the rubber-like polymer (A) in the polyorganosiloxane-containing graft polymer (B) is preferably in the range of 50 to 95% by mass, more preferably 70 to 94% by mass, from the viewpoint of the impact strength of the molded article. %, more preferably 70 to 90% by mass, most preferably 75 to 90% by mass.
Further, the mass ratio (A1/A2) of the polyorganosiloxane (A1) and the vinyl polymer (A2) in the rubber-like polymer (A) is 70 from the viewpoint of the refractive index of the polymer and the impact strength of the molded article. /30 to 30/70, more preferably 60/40 to 40/60.

The polyorganosiloxane-containing graft polymer (B) can be obtained by adding the vinyl monomer (b) and graft-polymerizing it in the presence of rubber latex.

The glass transition temperature of the polymer comprising the vinyl monomer (b) graft-polymerized to the rubber-like polymer (A) is preferably 70°C or higher, more preferably 80°C or higher, and is in the range of 90 to 105°C. It is even more preferable to have For example, a copolymer of methyl methacrylate and butyl acrylate tends to have a glass transition temperature in the range of 90 to 105° C., and these monomers can be suitably used as the vinyl monomer (b).

(emulsifier)
The emulsifier used in the production method is not particularly limited, but an anionic emulsifier or a nonionic emulsifier is preferable.

Examples of anionic emulsifiers include sodium alkylbenzenesulfonate, sodium alkyldiphenylether disulfonate, sodium alkylsulfate, sodium polyoxyethylene alkylsulfate, and sodium polyoxyethylene nonylphenyl ether sulfate.

Examples of nonionic emulsifiers include the following. polyoxyethylene alkyl ether, polyoxyethylene alkylene alkyl ether, polyoxyethylene distyrenated phenyl ether, polyoxyethylene tribenzylphenyl ether, polyoxyethylene polyoxypropylene glycol and the like.

Other examples include polyoxyalkylene alkylphenyl ether phosphates and polyoxyalkylene alkyl ether phosphates, preferably polyoxyethylene alkylphenyl ether phosphates and polyoxyethylene alkyl ether phosphates, more preferably poly Oxyethylene alkyl ether phosphate and the like can be mentioned. Moreover, these emulsifiers can be used individually by 1 type or in combination of 2 or more types.

The amount of the emulsifier used is preferably in the range of 0.05 to 10 parts by weight, preferably 0.1 to 5 parts by weight, relative to 100 parts by weight of the monomer forming the polyorganosiloxane-containing graft polymer (B). more preferably in the range of The particle size of the latex of the polyorganosiloxane-containing graft polymer (B) can be adjusted to a desired value by adjusting the amount of emulsifier used. When the amount of the emulsifier used is 0.05 parts by mass or more, the stability of various emulsions such as core latex, rubber latex and graft latex can be sufficiently improved. If the amount of the emulsifier is 10 parts by mass or less, the amount of the emulsifier remaining in the powder of the graft copolymer (B) can be sufficiently reduced. It is possible to suppress deterioration of thermal decomposition resistance and surface appearance of a molded article using a resin composition containing the above.

(Powder recovery step)
When recovering the powder of the graft copolymer (B) from the latex of the graft copolymer (B), either a spray drying method or a coagulation method can be used.

The spray-drying method is a method in which the latex of the graft copolymer is sprayed into a dryer in the form of fine droplets, which are then dried by applying a heated gas for drying. Methods for generating fine droplets include, for example, a rotating disc type, a pressure nozzle type, a two-fluid nozzle type, and a pressurized two-fluid nozzle type. The capacity of the dryer can be from small capacity for laboratory use to large capacity for industrial use. The temperature of the heating gas for drying is preferably 200°C or less, more preferably 120 to 180°C. Latices of two or more graft copolymers made separately can also be spray dried together. Furthermore, in order to improve powder properties such as blocking and bulk specific gravity during spray drying, optional components such as silica may be added to the latex of the graft copolymer and spray drying may be carried out.

The coagulation method is a method of coagulating the latex of the graft copolymer (B), separating the graft copolymer (B), recovering it, and drying it. First, a graft copolymer latex is put into hot water in which a coagulant is dissolved, salted out, and coagulated to separate the graft copolymer. Next, the separated wet graft copolymer is recovered by dehydration or the like to reduce the water content. The recovered graft copolymer is dried using a press dehydrator or a hot air dryer.

The coagulant includes inorganic salts such as aluminum chloride, aluminum sulfate, sodium sulfate, magnesium sulfate, sodium nitrate and calcium acetate, and acids such as sulfuric acid, with calcium acetate being particularly preferred. These coagulants can be used singly or in combination of two or more, but when using two or more, it is necessary to select a combination that does not form a water-insoluble salt. For example, the combined use of calcium acetate and sulfuric acid or its sodium salt forms a water-insoluble calcium salt, which is not preferred.

The above coagulants are usually used as aqueous solutions. From the viewpoint of stably coagulating and recovering the graft copolymer, the concentration of the coagulant aqueous solution is preferably 0.1% by mass or more, particularly 1% by mass or more. Further, from the viewpoint of reducing the amount of the coagulant remaining in the recovered graft copolymer and preventing deterioration of the molding appearance of the molded article, the concentration of the coagulant aqueous solution is 20% by mass or less, particularly 15% by mass. The following are preferable. Although the amount of the aqueous coagulant solution is not particularly limited, it is preferably 10 parts by mass or more and 500 parts by mass or less with respect to 100 parts by mass of latex.

The method of bringing the latex into contact with the aqueous coagulant solution is not particularly limited, but the following methods are usually used. (1) A method in which latex is continuously added to an aqueous coagulant solution while it is stirred and held for a certain period of time; A method in which a mixture containing the coagulated polymer and water is continuously withdrawn from the container while being injected into the container. Although the temperature at which the latex is brought into contact with the aqueous coagulant solution is not particularly limited, it is preferably 30°C or higher and 100°C or lower. Contact time is not particularly limited.

The coagulated graft copolymer is washed with about 1 to 100 times the weight of water, and the filtered wet graft copolymer is dried using a fluidized dryer, a dehydrator or the like. The drying temperature and drying time may be appropriately determined according to the graft copolymer to be obtained. In addition, without recovering the graft copolymer discharged from the dehydrator or extruder, it is also possible to directly send it to an extruder or molding machine for producing a resin composition, and mix it with a thermoplastic resin to obtain a molded product. It is possible.

(resin composition)
The resin composition of the present invention contains a thermoplastic resin (C) and a polyorganosiloxane-containing graft polymer (B). Many thermoplastic resins, including vinyl chloride resins and olefin resins such as polyethylene, use a resin modifier containing methyl methacrylate as a main component. A polyorganosiloxane-containing graft polymer (B) having

The thermoplastic resin (C) contained in the resin composition of the present invention is not particularly limited. A polar polymer, a halogen-based polymer such as a vinyl chloride resin, an acrylic resin, or the like can be applied.

Engineering plastics are not particularly limited as long as they are known various thermoplastic engineering plastics, and polyester polymers such as polyphenylene ether, polycarbonate, polyethylene terephthalate, and polybutylene terephthalate, syndiotactic polystyrene, 6-nylon, 6,6 -Nylon-based polymers such as nylon, polyarylate, polyphenylene sulfide, polyetherketone, polyetheretherketone, polysulfone, polyethersulfone, polyamideimide, polyetherimide, polyacetal and the like.

Special styrene resins such as heat-resistant ABS and heat-resistant acrylic resins, which are highly heat-resistant and require melt fluidity, can also be exemplified as engineering plastics in the present invention. Among these, aromatic polycarbonates and polybutylene terephthalate, which are more required to develop strength, are more preferable. Examples of the aromatic polycarbonates include 4,4'-dioxydiarylalkane-based polycarbonates such as 4,4'-dihydroxydiphenyl-2,2-propane (that is, bisphenol A)-based polycarbonates.

Olefin resins include high-density polyethylene, medium-density polyethylene, low-density polyethylene, copolymers of ethylene and other α-olefins; polypropylene, copolymers of propylene and other α-olefins; polybutene, poly- 4-methylpentene-1 and the like.

Thermoplastic elastomers include styrene-butadiene-styrene copolymer (SBS), styrene-isoprene-styrene copolymer (SIS), styrene-ethylene-butene copolymer (SEB), and styrene-ethylene-propylene copolymer. (SEP), styrene-ethylene-butene-styrene copolymer (SEBS), styrene-ethylene-propylene-styrene copolymer (SEPS), styrene-ethylene-ethylene-propylene-styrene copolymer (SEEPS), styrene- Butadiene-butylene-styrene copolymer (partially hydrogenated styrene-butadiene-styrene copolymer: SBBS), partially hydrogenated styrene-isoprene-styrene copolymer, styrene-isoprene-butadiene-styrene copolymer styrene elastomers such as partially hydrogenated products, polymer diols (polyester diols, polyether diols, polyester ether diols, polycarbonate diols, polyester polycarbonate diols, etc.), organic diisocyanates (organic diisocyanates include 4,4'-diphenylmethane diisocyanate , toluene diisocyanate, p-phenylene diisocyanate, xylylene diisocyanate, naphthalene diisocyanate, hydrogenated 4,4′-diphenylmethane diisocyanate (4,4′-dicyclohexylmethane diisocyanate), isophorone diisocyanate, hexamethylene diisocyanate, etc. 4,4'-diphenylmethane diisocyanate among the organic diisocyanates) and chain extenders (ethylene glycol, diethylene glycol, 1,4-butanediol, 1,5-pentanediol, 2-methyl-1,3-propanediol, 1 ,6-hexanediol, neopentyl glycol, 1,9-nonanediol, cyclohexanediol, 1,4-bis(β-hydroxyethoxy)benzene, etc.), ethylene-propylene rubber , ethylene-propylene-diene rubber, ethylene-vinyl acetate copolymer, butyl rubber, butadiene rubber, propylene-butene copolymer, ethylene-acrylate copolymer and other polyolefin elastomers, polyamide elastomers, fluorine elastomers, chlorinated PE system elastomers, acrylic elastomers, and the like.

Styrene-based resins include polystyrene, acrylonitrile-styrene copolymer, acrylonitrile-styrene-α-methylstyrene copolymer, acrylonitrile-methyl methacrylate-styrene-α-methylstyrene copolymer, ABS resin, AS resin, MABS resin. , MBS resin, AAS resin, AES resin, acrylonitrile-butadiene-styrene-α-methylstyrene copolymer, acrylonitrile-methyl methacrylate-butadiene-styrene-α-methylstyrene copolymer, styrene-maleic anhydride copolymer, Styrene-maleimide copolymer, styrene-N-substituted maleimide copolymer, acrylonitrile-styrene-N-substituted maleimide copolymer, acrylonitrile-butadiene-styrene-β-isopropenylnaphthalene copolymer, and acrylonitrile-methyl methacrylate- butadiene-styrene-α-methylstyrene-maleimide copolymer and the like. Each of these may be contained alone, or two or more thereof may be contained.

Polyester is a polymer composed of a polybasic acid and a polyhydric alcohol, and is not particularly limited as long as it has thermoplasticity. Examples of polybasic acids include terephthalic acid, naphthaldicarboxylic acid, cyclohexyldicarboxylic acid, and esters thereof. Examples of polyhydric alcohols include ethylene glycol, propylene glycol, butanediol, pentanediol, neopentyl glycol, and hexane. diol, octanediol, decanediol, cyclohexanedimethanol, hydroquinone, bisphenol A, 2,2-bis(4-hydroxyethoxyphenyl)propane, 1,4-dimethyloltetrabromobenzene, TBA-EO and the like. The polyester resin may be a homopolymer, a copolymer, or a blend of two or more of these. In addition, the product name "PETG" manufactured by Eastman Chemical Co., Ltd. is also preferably used.

Biodegradable polymers include microbial polymers such as biopolyesters (PHB/V, etc.), bacterial cellulose, microbial polysaccharides (pullulan, curdlan, etc.), and aliphatic polyesters (polycaprolactone, polybutylene succinate, polyethylene succinate, etc.). , polyglycolic acid, polylactic acid, etc.), polyvinyl alcohol, polyamino acids (PMLG, etc.) and other chemically synthesized polymers, and natural product polymers such as chitosan/cellulose, starch, and cellulose acetate.

Examples of halogenated polymers include homopolymers of vinyl chloride, copolymers containing 80% by weight or more of vinyl chloride, and vinyl chloride resins such as highly chlorinated polyvinyl chloride. Copolymer components include, in addition to vinyl chloride, monovinylidene compounds such as ethylene, vinyl acetate, methyl methacrylate, and butyl acrylate. These compounds may be contained in the copolymer in a total amount of 20% by weight or less. The above homopolymers and copolymers may be contained singly or in combination of two or more. Fluorinated polymers, brominated polymers, iodinated polymers and the like are also included.

Examples of acrylic resins include copolymers obtained by polymerizing vinyl monomers copolymerizable with methyl methacrylate. Examples of the copolymerizable vinyl monomer include alkyl acrylates such as methyl acrylate, ethyl acrylate, i-propyl acrylate, n-butyl acrylate and 2-ethylhexyl acrylate, ethyl methacrylate, propyl methacrylate and n-butyl methacrylate. Aromatic vinyl compounds such as alkyl methacrylate, styrene, α-methylstyrene and vinyltoluene can be used.

Polyester resins such as polyphenylene ether, polycarbonate, polyethylene terephthalate and polybutylene terephthalate, polyamide resins such as syndiotactic polystyrene, 6-nylon and 6,6-nylon, polyarylate, polyphenylene sulfide, polyether ketone, polyether ether Polymer alloys of engineering plastics such as ketones, polysulfones, polyethersulfones, polyamideimides, polyetherimides and polyacetals and the thermoplastic resins described above are also included in the scope of the present invention.

In addition to the above materials, the resin composition of the present invention may contain various known additives such as stabilizers, flame retardants, flame retardant aids, hydrolysis inhibitors, electrification Inhibitors, blowing agents, dyes, pigments and the like can be included.

The method of blending each material when preparing the resin composition of the present invention includes a known blending method, and is not particularly limited. Examples thereof include a method of mixing and kneading with a tumbler, V-type blender, super mixer, Nauta mixer, Banbury mixer, kneading roll, extruder, or the like.

The resin composition of the present invention can be produced by mixing a thermoplastic resin, a polyorganosiloxane-containing graft polymer (B), and, if necessary, additives. Specifically, for example, a pellet-shaped thermoplastic resin, a polyorganosiloxane-containing graft polymer (B), and, if necessary, an additive are mixed using an extruder, extruded into a strand, and a rotary cutter or the like is used. A resin composition can be obtained by cutting into pellets.

The content of the polyorganosiloxane-containing graft polymer (B) in the resin composition of the present invention is 0.5 to 30% by mass in the total 100% by mass of the thermoplastic resin and the polyorganosiloxane-containing graft polymer (B). is preferably in the range of , more preferably in the range of 1 to 20% by mass, and even more preferably in the range of 2 to 15% by mass. When this content is 0.5% by mass or more, the molded article obtained is excellent in impact resistance and appearance. Further, when the content is 30% by mass or less, sufficient fluidity of the resin composition and mechanical properties of the molded article can be obtained.

(Molded body)
Examples of the method for molding the resin composition of the present invention include molding methods commonly used for molding thermoplastic resin compositions, such as injection molding, extrusion molding, blow molding and calendar molding.

The molded article of the present invention can be widely used industrially as various materials in the fields of automobiles, OA equipment, household appliances, electric/electronics, and the like. More specifically, it can be used as housings for electronic devices, various parts, automobile structural members, automobile interior parts, and light reflectors. More specifically, it can be used as an interior/exterior member for personal computer housings, mobile phone housings, portable information terminal housings, portable game machine housings, printers, copiers, and the like.

The present invention will be described in more detail below with reference to production examples and examples. Production Examples 1 to 3 are production examples of rubber-like polymer (A) and polyorganosiloxane-containing graft polymer (B). In addition, "part" means "mass part" and "%" means "mass %".

<Production Example 1> (Production of polyorganosiloxane-containing graft polymer)
In a separable flask equipped with a condenser, a thermometer and a stirrer, "component 1" consisting of water and an emulsifier shown in Table 1 was added. The atmosphere in the flask was replaced with nitrogen by passing a stream of nitrogen through the separable flask, and the liquid temperature was raised to 80°C. When the liquid temperature reached 80° C., the seed monomer "Component 2" shown in Table 1 was mixed, and after stirring for 5 minutes, the polymerization initiator "Component 3" shown in Table 1 was added to initiate polymerization. (The maximum temperature may rise by about 10°C due to heat generated by polymerization). Thereafter, the liquid temperature was kept fixed for 25 minutes so as not to fall below 78°C.

Next, the core-forming monomer “Component 4” shown in Table 1 was forcibly emulsified and dropped into the separable flask while controlling the liquid temperature at 80±2° C. over 240 minutes. After that, the liquid temperature was maintained at 80° C.±2° C. for 60 minutes. A core latex was thus obtained. The particle diameter of the core latex at this time was 90 nm as a result of measurement by a light scattering method. The polymerization rate was 99%.

Subsequently, "Component 5", "Component 6" and "Component 7" shown in Table 1 were added in order. After confirming that the pH in the polymerization system was 1.5 to 2.5 at 20°C, the liquid temperature was raised to 85°C.

Next, the organosiloxane polymer-forming monomer "Component 8" shown in Table 1 was forcibly emulsified and added dropwise into the separable flask over 240 minutes while controlling the liquid temperature at 85±2°C. Then, the liquid temperature was maintained at 85° C.±2° C. for 120 minutes. After that, about 1.5 to 4 parts by mass of a 10% sodium hydroxide aqueous solution was added, and the pH in the polymerization system was confirmed to be 7.0 to 8.0 at 20°C. The particle size of the rubber-like polymer in the rubber latex at this time was 105 nm as a result of measurement by a light scattering method. The polymerization rate was 93%.

After that, the liquid temperature was adjusted to 80°C, "Component 9" shown in Table 1 was added, and the mixture was maintained at 80°C ± 2°C for 5 minutes. After that, "Component 10" was added, and the temperature was maintained at 80°C ± 2°C for 25 minutes. Since the amounts of ferrous sulfate and disodium ethylenediaminetetraacetic acid to be blended were small, component 10 was blended in 10 times the amount, and 1/10 of the amount was weighed and added to the latex. The graft-forming monomer "Component 11" was forcibly emulsified and added dropwise into the separable flask over 60 minutes while controlling the liquid temperature at 80±2°C. After that, the liquid temperature was maintained at 80° C.±2° C. for 60 minutes. The particle size of the graft latex at this time was 110 nm as a result of measurement by a light scattering method. The rate of polymerization was determined by measuring the residual rate of the graft monomer component with a gas chromatograph.

An aqueous solution containing 500 parts of deionized water and 5 parts of calcium acetate was set at a temperature of 40° C.±5° C., and the graft latex was added to the aqueous solution to form a slurry. The liquid temperature was raised to 70° C.±5 and held for 5 minutes to coagulate the slurry. The aggregates are collected, immersed in 1,500 parts of deionized water, and the process of dehydration is repeated twice, dried at a temperature of 65 ° C. ± 5 for 12 hours, and polyorganosiloxane-containing graft polymer (rubber-containing graft polymer: P- 1) powder was obtained.

As sodium dodecylbenzenesulfonate, the trade name "Neopelex G-15" manufactured by KAO (16% aqueous solution of sodium dodecylbenzenesulfonate) was used.
As the sodium dialkylsulfosuccinate, the trade name "Pelex OT-P" manufactured by KAO (80% sodium dialkylsulfosuccinate solution in methanol) was used.
As t-butyl hydroperoxide, trade name "PERBUTYL H-69" manufactured by NOF (69% aqueous solution of t-butyl hydroperoxide) was used.

<Production Example 2> (Production of polyorganosiloxane-containing graft polymer)
As shown in Table 1, a polyorganosiloxane-containing graft polymer (rubber-containing graft polymer: P-2) was produced in the same manner as in Production Example 1, except that 3-methacryloxypropylmethyldimethoxysilane was not blended in the components forming the core latex. powder was obtained. The polymerization rate and particle size of the rubber latex and graft latex did not change significantly from those in Production Example 1.

<Production Example 3> (Production of acrylic rubber-containing graft polymer)
In a separable flask equipped with a condenser, a thermometer and a stirrer, "component 1" consisting of water and an emulsifier shown in Table 2 was added. The atmosphere in the flask was replaced with nitrogen by passing a stream of nitrogen through the separable flask, and the liquid temperature was raised to 80°C. When the liquid temperature reached 80° C., the seed monomer "Component 2" shown in Table 2 was mixed, and after stirring for 5 minutes, the polymerization initiator "Component 3" shown in Table 2 was added to initiate polymerization. (The maximum temperature may rise by about 10°C due to heat generated by polymerization). Thereafter, the liquid temperature was kept fixed for 25 minutes so as not to fall below 78°C.

Next, the rubber-forming monomer "Component 4" shown in Table 2 was forcibly emulsified and added dropwise into the separable flask over 180 minutes while controlling the liquid temperature at 80±2°C. After that, the liquid temperature was maintained at 80° C.±2° C. for 60 minutes. Thus, a rubber-like polymer latex was obtained. The particle size of the rubber-like polymer latex at this time was 200 nm as a result of measurement by a light scattering method. The polymerization rate was 99%.

Subsequently, "Component 5" of the redox material shown in Table 2 was blended. Since the amounts of ferrous sulfate and disodium ethylenediaminetetraacetic acid to be blended were small, 10 times the amount of component 5 was blended, and 1/10 of the amount was weighed and added to the rubber latex. After that, the liquid temperature was maintained at 80° C.±2° C. for 5 minutes. The graft-forming monomer "Component 6" was added dropwise over 30 minutes while controlling the liquid temperature at 80±2°C. After that, the liquid temperature was maintained at 80° C.±2° C. for 60 minutes. Thus, an acrylic rubber-based graft latex was obtained. The particle diameter of the acrylic rubber-based graft latex at this time was 205 nm as a result of measurement by a light scattering method. The polymerization rate was 99.5%.

An aqueous solution containing 500 parts of deionized water and 5 parts of calcium acetate was set at a temperature of 40° C.±5° C., and the acrylic rubber-based graft latex was added to the aqueous solution to form a slurry. The liquid temperature was raised to 70° C.±5 and held for 5 minutes to coagulate the slurry. The aggregates are collected, immersed in 1,500 parts of deionized water, and dehydrated twice, dried at a temperature of 65° C.±5 for 12 hours, and acrylic rubber-containing graft polymer (rubber-containing graft polymer: P-3 ) powder was obtained.

As sodium dodecylbenzenesulfonate, the trade name "Neopelex G-15" manufactured by KAO (16% aqueous solution of sodium dodecylbenzenesulfonate) was used.
As the sodium dialkylsulfosuccinate, the trade name "Pelex OT-P" manufactured by KAO (80% sodium dialkylsulfosuccinate solution in methanol) was used.
As t-butyl hydroperoxide, trade name "PERBUTYL H-69" manufactured by NOF (69% aqueous solution of t-butyl hydroperoxide) was used.

[Measurement of polymerization rate]
The polymerization rate of each latex was measured by the following procedure.
(i) Measure the mass (x) of the aluminum pan to the nearest 0.1 mg.
(ii) About 1 g of the polymer (X) latex is placed in an aluminum dish, and the mass (y) of the aluminum dish containing the polymer (X) latex is measured to the nearest 0.1 mg.
(iii) Place the aluminum dish containing the latex of polymer (X) in a dryer at 180° C. and heat for 45 minutes.
(iv) Remove the aluminum pan from the dryer, cool to room temperature in a desiccator, and measure its mass (z) to the nearest 0.1 mg.
(v) Calculate the solid content concentration (%) of the latex of the polymer (X) based on the following formula.
Solid content concentration (%) = {(zx) / (yx)} x 100
(vi) The percentage (%) of the solid content concentration calculated by (v) with respect to the solid content concentration when all the monomers charged when producing the polymer (X) are polymerized, and the polymerization at the end of the graft latex production rate.

[Measurement of polyorganosiloxane]
Polyorganosiloxane in the rubber-containing graft polymers (P-1, P-2) was measured by fluorescent X-ray bulk calibration curve method. The results are listed in Table 4. The rubber-containing graft polymer (P-3) of Production Example 3 did not use an organosiloxane component during its production.

[Composition analysis derived from vinyl monomers other than polyorganosiloxane]
The polymer composition ratio was measured at a pyrolysis temperature of 500° C. using pyrolysis GC (gas chromatograph) or pyrolysis GC-MS (gas chromatograph-mass spectrometer). An ampoule-polymerized product was used as a standard polymer for calculation. The results are listed in Table 4. In Table 4, "PMMA" indicates polymethyl methacrylate, "PBA" indicates polybutyl acrylate, and "PSt" indicates polystyrene.

[Measurement of THF insoluble matter]
For the rubber-containing graft polymers (P-1, P-2, P-3) obtained in Production Examples 1 to 3, the THF-insoluble content was measured according to the following method. Table 4 shows the results.
It is measured by preparing a mixed solution of 1% by mass of the polyorganosiloxane-containing graft polymer (B) and 99% by mass of THF and performing the following operation.
(1) Add 0.5 g of sample to 50 ml of THF and extract at room temperature for 8 hours or more.
(2) On the day of the centrifugation operation, stir and extract (at room temperature) for 30 minutes or longer using a stirrer.
(3) The mixed solution is placed in a centrifugal tube and centrifuged at 16000 rpm for 40 minutes.
(4) After removing the supernatant, add THF and centrifuge again to wash out the insoluble matter. (repeat twice)
(5) After removing the supernatant liquid, the insoluble matter (including the centrifugal tube) is dried at a temperature of 80 ° C. for 8 hours, and further dried at 65 ° C. for 6 hours in a vacuum dryer. obtain.
The mass of the obtained dried sample (including the centrifugal tube) is measured, and the content ratio w _ais (%) of the THF-insoluble matter is calculated by the following formula.
w _ais =(w _c1 −w _as )/wt×100
wt: Mass of polyorganosiloxane-containing graft polymer (B) subjected to measurement (including THF-insoluble matter)
w _as : Mass of centrifuge tube w _c1 : Mass of THF-insoluble matter (mass including centrifuge tube)

[Measurement of refractive index]
Polydimethylsiloxane (refractive index: 1.40, specific gravity: 0.97) obtained in the above [measurement of polyorganosiloxane] and [composition analysis derived from vinyl monomers other than polyorganosiloxane], polymethyl methacrylate (refractive index 1.49, specific gravity: 1.20), polystyrene (refractive index 1.59, specific gravity: 1.05), poly n-butyl acrylate (refractive index 1.47, specific gravity: 1.09) weight ratio was converted to a volume ratio and multiplied by each refractive index to calculate the refractive index of the rubber-containing graft polymer (P-1, P-2, P-3). Table 4 shows the refractive indices obtained.

[Core structure ratio]
Polyorganosiloxane-containing graft polymers (rubber-containing graft polymers P-1 and P-2) were placed in a polyethylene capsule, and epoxy resin Epiform (manufactured by Somar Co., Ltd.) was poured into the capsule and stirred. It was left at room temperature for 12 hours to cure the epoxy resin. The resulting resin pieces were leveled and trimmed using an ultramicrotome Leica EM UC7 (manufactured by Leica Microsystems, Inc.). Subsequently, by the freezing microtome method, sections were cut under the conditions of -100°C cutting temperature, 0.4 mm/sec cutting speed, and 50 nm thickness, and collected on a copper grid with a support film.

Images were obtained with a transmission electron microscope H-7600 (manufactured by Hitachi Ltd.) at an acceleration voltage of 80 kV and a magnification of 100,000. Among the particles confirmed in the image, 30% of the particles having the largest cross-sectional area were selected, and a total of 100 or more particles were evaluated. Even without dyeing, the polyorganosiloxane (A1) is confirmed with a dark contrast and the vinyl polymer (A2) with a bright contrast. Particles are classified into five types shown in FIG. 1. Among them, the number of particles having a core structure (S structure) as shown in S in FIG. 1 is counted, and the ratio to the number of particles to be evaluated is calculated. bottom. The results are summarized in Tables 3 and 4. In FIG. 1, the dark-colored portion indicates the phase region derived from the polyorganosiloxane (A1), and the light-colored portion indicates the phase region derived from the vinyl polymer (A2) (styrene in Production Examples 1 and 2).
The rubber-containing graft polymer (P-3) of Production Example 3 did not use a core-forming component during its production, so the core structure ratio in Table 4 was set to "0." Table 3 also shows the proportions of T-structure, U-structure, V-structure, and W-structure particles together with the proportion of S-structure grains.

Among the particles confirmed in the image obtained by the above measurement, 30% (based on the number) of particles with the largest cross-sectional area were selected. Product name: Image Pro Plus) was used to calculate the average particle size. Table 4 shows the respective values of the polyorganosiloxane-containing graft polymers (rubber-containing graft polymers P-1 and P-2).

[Example 1, Comparative Examples 1 and 2]
5 parts by mass of the rubber-containing graft polymers (P-1, P-2, P-3) obtained in Production Examples 1 to 3, an aromatic polycarbonate ("Taflon FN-1500" (trade name), manufactured by Idemitsu Kosan Co., Ltd. , and a nominal aromatic polycarbonate resin Mv: 15,000) were blended in an amount of 95 parts by mass to obtain a mixture. This mixture was supplied to a devolatilizing twin-screw extruder (manufactured by Ikegai Iron Works Co., Ltd., PCM-30 (trade name)) heated to a barrel temperature of 280° C. and kneaded to blend 5% by mass of a rubber-containing graft polymer. A pellet of the resin composition was prepared.

[Charpy impact test]
Each pellet is separately supplied to a Sumitomo injection molding machine SE100DU (trade name) (manufactured by Sumitomo Heavy Industries, Ltd.), and the cylinder temperature is 280 ° C. and the mold temperature is 80 ° C. Length 80 mm × width 10 mm × thickness A compact (test piece) with a thickness of 4 mm was obtained. The Charpy impact test conforms to ISO-179-1 and is measured at 23°C and -30°C with TYPEA notches conforming to ISO2818. Table 4 shows the measurement results.

[Transmittance]
In accordance with JIS K 7375, using a HAZE Meter NDH4000 (trade name) manufactured by Nippon Denshoku Industries Co., Ltd., a test piece (length 100 mm, width 50 mm, thickness 2 mm) was measured for total light transmittance in a D65 light source. It was measured. The higher the total light transmittance, the higher the color developability when a pigment or the like is added, so it was judged to be good. Table 4 shows the measurement results. The test piece for transmittance measurement was obtained in the same manner as the test piece for Charpy impact test except that the size was different.

The resin composition obtained in Example 1 sufficiently contained a polyorganosiloxane-containing graft polymer having a core structure as the rubber-containing graft polymer, and the polyorganosiloxane in this polymer was sufficiently crosslinked and the core was Covalent bonding to the core of the structure is sufficient. Therefore, Example 1 was superior to Comparative Example 1 in impact strength and transmittance.

The polyorganosiloxane-containing graft polymer (P-1) used in Example 1 has substantially the same refractive index as the polyorganosiloxane-containing graft polymer (P-3) (so-called acrylic rubber graft polymer) used in Comparative Example 2. As for the transmittance of the resin composition, Example 1 is superior.

In addition, the molded article of the resin composition containing the acrylic rubber graft polymer of Comparative Example 2 has low impact strength at low temperatures. In contrast, the resin composition containing the polyorganosiloxane-containing graft polymer having the core structure of Example 1 has improved impact strength at a constant temperature of the molded product.

[Example 2, Comparative Example 3]
5 parts by mass of the rubber-containing graft polymers (P-1, P-2) obtained in Production Examples 1 and 2, an aromatic polycarbonate ("Iupilon S-2000" (trade name), Mitsubishi Engineering-Plastics Co., Ltd. 80 parts by mass of a nominal aromatic polycarbonate resin Mv: 23,000) and 15 parts by mass of a styrene-acrylonitrile copolymer (“AP-H” (trade name), manufactured by Techno UMG Co., Ltd.). , to obtain a mixture. This mixture was supplied to a devolatilizing twin-screw extruder (manufactured by Ikegai Iron Works Co., Ltd., PCM-30 (trade name)) heated to a barrel temperature of 260° C. and kneaded to blend 5% by mass of a rubber-containing graft polymer. A pellet of the resin composition was prepared. Each pellet is separately supplied to a Sumitomo injection molding machine SE100DU (trade name) (manufactured by Sumitomo Heavy Industries, Ltd.), and the cylinder temperature is 260 ° C. and the mold temperature is 70 ° C. Length 80 mm × width 10 mm × thickness A compact (test piece) with a thickness of 4 mm was obtained.

[Example 3, Comparative Example 4]
10 parts by mass of the rubber-containing graft polymers (P-1, P-2) obtained in Production Examples 1 and 2, polybutylene terephthalate ("Novaduran 5010R5" (trade name), manufactured by Mitsubishi Engineering-Plastics Corporation) was blended to obtain a mixture. This mixture was supplied to a devolatilizing twin-screw extruder (manufactured by Ikegai Iron Works Co., Ltd., PCM-30 (trade name)) heated to a barrel temperature of 270° C. and kneaded, and 10% by mass of the rubber-containing graft polymer was blended. A pellet of the resin composition was prepared. Each pellet is separately supplied to a Sumitomo injection molding machine SE100DU (trade name) (manufactured by Sumitomo Heavy Industries, Ltd.), and the cylinder temperature is 260 ° C. and the mold temperature is 60 ° C. Length 80 mm × width 10 mm × thickness A compact (test piece) with a thickness of 4 mm was obtained. Similarly, a molded body (test piece) having a length of 100 mm, a width of 50 mm, and a thickness of 2 mm was obtained.

[Charpy impact test]
Notches of TYPEA conforming to ISO-179-1 and conforming to ISO2818 were cut, and the obtained compact (length 80 mm, width 10 mm, thickness 4 mm) was measured at 23°C and -30°C. Table 5 shows the measurement results. "N.B." in the table means "non-destructive".

[Transmittance]
In accordance with JIS K 7375, using a HAZE Meter NDH4000 (trade name) manufactured by Nippon Denshoku Industries Co., Ltd., a test piece (length 100 mm, width 50 mm, thickness 2 mm) was measured for total light transmittance in a D65 light source. It was measured. The higher the total light transmittance, the higher the color developability when a pigment or the like is added, so it was judged to be good. Table 5 shows the measurement results.

The resin composition obtained in Example 2 sufficiently contained a polyorganosiloxane-containing graft polymer having a core structure as a rubber-containing graft polymer, and the polyorganosiloxane in this polymer was sufficiently crosslinked and the core was Covalent bonding to the core of the structure is sufficient. Therefore, Example 2 was superior to Comparative Example 3 in impact strength and transmittance.

The resin composition obtained in Example 3 sufficiently contained a polyorganosiloxane-containing graft polymer having a core structure as the rubber-containing graft polymer, and the polyorganosiloxane in this polymer was sufficiently crosslinked and the core was Covalent bonding to the core of the structure is sufficient. Therefore, Example 3 was superior to Comparative Example 4 in impact strength and transmittance.

Thus, according to the present invention, as the rubber-containing graft polymer, the polyorganosiloxane-containing graft polymer having a core structure with a particle size of 50 to 250 nm can be uniformly dispersed in the thermoplastic resin, and the strength of the molded product can be improved. and appearance can be improved.

Claims (17)

Latex polymer particles comprising a polymer (A) containing a polyorganosiloxane (A1) and a vinyl polymer (A2) are a polyorganosiloxane-containing graft polymer grafted with a vinyl monomer (b). hand,
The polyorganosiloxane (A1) is a polymer containing units of organosiloxane (a1), the organosiloxane (a1) is a cyclic dimethylsiloxane and/or a difunctional dialkylsilane compound,
The vinyl polymer (A2) is styrene, α-methylstyrene, phenyl methacrylate, acrylonitrile, vinylidene chloride, p-chlorostyrene, benzyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, 3,3,5-trimethylcyclohexyl methacrylate, isobornyl A monomer polymer containing at least one vinyl monomer (a2-1) selected from the group consisting of acrylate, isobornyl methacrylate, methyl methacrylate, pt-butylstyrene, and n-butyl acrylate,
The vinyl monomer (b) comprises methyl methacrylate,
The mass ratio (A1/A2) of the polyorganosiloxane (A1) and the vinyl polymer (A2) in the polymer (A) is in the range of 70/30 to 30/70,
A polyorganosiloxane-containing graft polymer (B) that satisfies the following requirements Z-1 to Z-4.
Z-1) Particles having a structure in which the vinyl polymer (A2) is contained solely in the polyorganosiloxane (A1) account for 15% or more in number average Z-2) Polyorganosiloxane-containing graft polymer (B) Z-3) The particle size of the polyorganosiloxane-containing graft polymer (B) is 50 to 250 nm.
Z-4) The refractive index of the polyorganosiloxane-containing graft polymer (B) is 1.47 to 1.60 2. The polyorganosiloxane-containing graft polymer (B) according to claim 1, wherein said vinyl polymer (A2) is a polymer of monomers containing styrene. 3. The polyorganosiloxane-containing graft according to claim 1, wherein the content of the vinyl monomer (a2-1) with respect to the total vinyl monomers constituting the vinyl polymer (A2) is 80% by mass or more. Polymer (B). The cyclic dimethylsiloxane as the organosiloxane (a1) is one or more cyclic siloxanes selected from hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, and dodecamethylcyclohexasiloxane. ,
wherein the bifunctional dialkylsilane compound as the organosiloxane (a1) is one or more silane compounds selected from dimethyldimethoxysilane, dimethyldiethoxysilane, diethoxydiethylsilane, and dipropoxydimethylsilane; Item 4. The polyorganosiloxane-containing graft polymer (B) according to any one of Items 1 to 3. The polyorganosiloxane according to any one of claims 1 to 4 , wherein the content of the polymer (A) in the polyorganosiloxane-containing graft polymer (B) is in the range of 50 to 95% by mass. Containing graft polymer (B). 6. The polyorganosiloxane-containing graft polymer ( B). The polyorganosiloxane-containing graft polymer (B) according to any one of claims 1 to 6, wherein the polymer comprising the vinyl monomer (b) has a glass transition temperature of 70°C or higher. 7. The polyorganosiloxane-containing graft polymer (B) according to any one of claims 1 to 6, wherein the polymer comprising the vinyl monomer (b) has a glass transition temperature of 90 to 105°C. The polymer (A) is a monomer containing an organosiloxane (a1) in the presence of a latex composed of a monomer polymer containing a vinyl monomer (a2-1) and a siloxane-based graft crossing agent (a2-2). 9. The polyorganosiloxane-containing graft polymer (B) according to any one of claims 1 to 8 , which is a polymer obtained by polymerizing a monomer. 10. The vinyl polymer (A2) according to any one of claims 1 to 9, wherein the vinyl polymer (A2) is a monomer polymer containing a vinyl monomer (a2-1) and a siloxane-based graft crossing agent (a2-2). The polyorganosiloxane-containing graft polymer (B) described in 1. The polyorganosiloxane-containing graft polymer (B) according to claim 9 or 10, wherein the siloxane-based graft crossing agent (a2-2) is a siloxane represented by the following formula (I).
R—Si(R ₁ ) _n (OR ₂ ) _(3-n) (I)
In formula (I), R ₁ represents a methyl group, an ethyl group, a propyl group, or a phenyl group. R. ₂ represents an organic group in an alkoxyl group, and represents a methyl group, an ethyl group, a propyl group, or a phenyl group; n represents 0, 1, or 2; R represents a methacryloyloxyalkyl group, a vinylphenyl group, a vinyl group; , or a mercaptoalkyl group. 12. The polyorganosiloxane-containing graft polymer (B) according to any one of claims 9 to 11, wherein the siloxane-based graft-crossing agent (a2-2) is 3-methacryloxypropylmethyldimethoxysilane. The content of the siloxane-based graft-crossing agent (a2-2) is 0.05 with respect to a total of 100% by mass of the vinyl monomer (a2-1) and the siloxane-based graft-crossing agent (a2-2). The polyorganosiloxane-containing graft polymer (B) according to any one of claims 9 to 12, in the range of -20% by weight. A resin composition comprising the polyorganosiloxane-containing graft polymer (B) according to any one of claims 1 to 13 and a thermoplastic resin (C). 15. The resin composition according to claim 14 , wherein said thermoplastic resin (C) comprises an aromatic polycarbonate. A molded article formed using the resin composition according to claim 14 or 15 . A method for producing the polyorganosiloxane-containing graft polymer (B) according to any one of claims 1 to 13,
forming a first polymer latex by emulsion polymerizing a monomer containing a vinyl monomer (a2-1) in a solvent in the presence of an emulsifier;
a step of adding an organosiloxane (a1) or a mixture containing the same to the first polymer latex to perform emulsion polymerization to form a second polymer latex comprising the polymer (A);
A method for producing a polyorganosiloxane-containing graft polymer (B), comprising the step of adding a vinyl monomer (b) to the second polymer latex to graft the polymer (A).

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